On the Robustness of Transmit Beamforming
2010 (English)In: IEEE Transactions on Signal Processing, ISSN 1053-587X, E-ISSN 1941-0476, Vol. 58, no 11, 5933-5938 p.Article in journal (Refereed) Published
Beamforming is a simple transmit strategy that uses only one eigen-direction in multiple-input multiple-output channels. This simplicity makes beamforming a competitive strategy in practice, but at the same time poses a doubt on the sensitivity of beamforming to the imperfectness of the channel state information at the transmitter (CSIT). This paper studies beamforming from the perspective of worst-case robustness. We show that beamforming can achieve the maximum received signal-to-noise ratio (SNR) or guarantees a given received SNR with the minimum transmit power, in the worst channel within an elliptical uncertainty region defined by the weighted spectral norm. This result further implies that beamforming has the ability to combat against the imperfectness of CSIT, especially for small channel dimensions or small channel uncertainty.
Place, publisher, year, edition, pages
2010. Vol. 58, no 11, 5933-5938 p.
Beamforming, imperfect CSIT, maximin, MIMO, worst-case robustness
IdentifiersURN: urn:nbn:se:kth:diva-101034DOI: 10.1109/TSP.2010.2066270ISI: 000283444600039ScopusID: 2-s2.0-79951629359OAI: oai:DiVA.org:kth-101034DiVA: diva2:547710
QC 201208282012-08-282012-08-222012-08-28Bibliographically approved